Conventional broadcast television operates by video content (e.g., television shows) being communicated over analog broadcast frequencies, commonly known as channels. Broadcasters of conventional television schedule the video content, commonly known as programming (hereinafter “video programming”), so that viewers of the television channels can watch a certain program at a certain time. For example, a broadcaster may schedule a television show on a certain day and at a certain time (e.g., Seinfeld, Thursday, 7:00 PM, Channel 5, ABC network). With conventional television being broadcast over public airwaves with high bandwidth, a viewer selects a channel on a television, which causes a television receiver to tune to a frequency associated with the selected channel. The television receiver receives broadcast signals being broadcast at that broadcast frequency. Once received, the television displays the video content being received on the channel. As is appreciated by conventional television viewers, the time between selecting a channel and displaying the video content of the channel is substantially instantaneous. And, as is appreciated by conventional television broadcasters, the cost to broadcast the video content to a large number of viewers (e.g., an entire city) is primarily limited to the cost of setting up a broadcast tower and video distribution equipment to that tower.
As the information age has developed, so has television. Viewership of conventional broadcast television has significantly decreased since cable and satellite television has become widely available. With cable and satellite networks, set top boxes were developed to operate as tuners and provide interactive programming guides for subscribers. The set top boxes operate by receiving digital signals representative of the content on each of the channels being communicated thereto. The set top boxes further operate by receiving and storing the programming guide information and enabling viewers to view the programming guide information to select a television channel by using a remote control that interacts with the set top box. Because the number of television channels has increased from less than ten with conventional television to hundreds of channels on both cable and satellite television, using the programming guide enables viewers to quickly browse through the television programs.
While the programming guide is helpful to viewers, there are viewers who want to casually browse the television programs being broadcast by simply changing the channels using an up and down channel selector on a remote control, as was traditionally done with conventional television before programming guides were available. This is commonly known as “channel surfing.” Channel surfing on televisions that have set top boxes is significantly slower than the channel surfing experience with conventional television. While display of video programming was substantially instantaneous with conventional broadcast television, display of video programming on set top box television (e.g., IPTV and satellite) has a delay of about two seconds. One reason for channel surfing being significantly slower than conventional television is the time delay for the set top boxes to request, access, and convert the digital content into viewable images. Another reason for the delay is the relatively low bandwidth of the communication mediums given the amount of data used for communicating the video content.
With the development of Internet protocol television (IPTV), communication companies are establishing networks for subscribers to watch video content. FIG. 1 is an illustration of a conventional network 100 that is configured to deliver IPTV. As shown, a head-end server 102 is used to store and deliver video content in the form of data packets 104 as data stream 105a and 105b (collectively 105), as understood in the art. An IPTV control server 106 is operable to manage and control the video content being streamed via the data stream 105 over the network 100 to subscribers. A data POP router 108 may be utilized to route the streaming video content to the appropriate locations over an IP network 110 (e.g., the Internet).
A digital subscriber line aggregator router 112 is configured to manage subscribers of a service provider. For example, a database (not shown) may store channel purchase information of a subscriber so that only those channels purchased by the subscriber are routed to that subscriber. As shown, the data stream 105 is communicated from the head-end server 102 via the data POP router 108 to the DSL aggregator router 112. The DSL aggregator router 112 communicates the data stream 105 via the IP network 110 to a DSL access multiplexer (DSLAM) 114. The DSLAM 114 operates to connect subscribers to the IP network 110, hosts video streams/Internet group management protocol (IGMP), and provides QnQ tagging for Ethernet transport of the video content. The DSLAM 114 further operates as a multiplexer to distribute the channels of the video stream 105 to modems 116a-116n (collectively 116) associated with set top boxes 118a-118n (collectively 118).
As with other forms of non-broadcast television, such as satellite and cable, video programming is also provided for subscribers to watch certain programs on certain days and at certain times. The set top boxes 118 are configured to download electronic programming guide (EPG) information from the video stream 105 and allow a subscriber to interact with the set top box 118a via a remote control (not shown) to view an electronic programming guide with the electronic programming guide information stored in the set top box.
While IPTV and other non-broadcast television platforms provide for improved television viewing, there are limitations to IPTV both on the network side and on the subscriber side. On the network side, and especially with IPTV networks, network providers make available a large number of the television channels (e.g., 200 or more channels). Of those channels, IPTV network providers typically continuously stream upwards of half (e.g., 80-100 channels) of the most popular channels to the DSLAM 114 via the data stream 105 to reduce latency for the viewer so that the viewer may “channel surf” as was traditionally done with broadcast television. While latency from the network to the set top box may be reduced by streaming the video programming, the time for the set top box to receive, convert, and display the video programming is still significantly longer than traditional broadcast television. As understood in the art, latency for selecting and displaying a channel is upwards of 2 seconds or more.
A problem with continuously streaming the large number of IPTV channels is the bandwidth needed used by the data being communicated over the network to the DSLAM. While traditional television image display uses bandwidth between 4 and 7 megabits per second (Mbps), high-definition television display uses between 12 and 14 Mbps. To manage the bandwidth being communicated over the network for both traditional and high-definition television display data streams, additional expensive equipment is deployed to handle the large bandwidth needs to meet ever increasing subscriber demand. Older DSLAMs with T1 IMA or DS3 interfaces cost roughly $20,000-$60,000 and can handle 8 Mbs-45 Mbs of bandwidth to service 48-672 customers, newer DSLAMS with OC3 or Gigabit Ethernet interfaces costs about $40,000-$100,000 and can handle 155 Mbs-1000 Mbps of bandwidth to service 672-1024 customers. As more subscribers transition to IPTV, much more equipment will be needed using the current philosophy of continuously streaming the most popular channels via the network to the DSLAMs to make the subscriber experience faster and more enjoyable.
On the subscriber side, subscribers using set top boxes with cable television, satellite television, and IPTV, for example, have the frustrating experience of having a slow channel surfing experience relative to conventional broadcast television. As previously described, the time needed for video programming to be displayed when switching to the channel, either via a programming guide or simply changing a channel using up or down channel selector from a remote control, may be 2 seconds or more. Such time delays, especially when compared to traditional broadcast television, feels like an eternity and weakens the television watching experience.